Remove per-stanza repo cache clear during testing.

This was not being used and is not supported by the equivalent C code.

test/lib/pgBackRestTest/Module/Command/CommandArchiveGetPerlTest.pm

@@ -52,7 +52,7 @@ sub initTest
     my $self = shift;
 
     # Clear cache from the previous test
-    storageRepoCacheClear($self->stanza());
+    storageRepoCacheClear();
 
     # Load options
     $self->configTestClear();